In the last few months, my laptop seems to be getting absolutely atrocious–and in some cases, impossible–battery time. It used to last 1.5-3 hours on battery depending upon what I was doing, and charged at a rate of about 1%/minute. Now I’m lucky if I can ever go half an hour on battery. And charging is much slower too.
Just today, it went from 86% charged to 4% charged in 6 minutes! That’s obviously impossible, so there might be some sort of error in reporting the battery level.
Can someone give me some ideas why I’m getting such crappy battery times, and what I can do to fix it? It’s a Dell Inspiron 4100.
Heat, whether ambient or caused by rapid charging, is the enemy of most rechargeable battery types, including NiCd, NiMH and to a lesser extent, Li-ion. Heating of the electrolyte leads to a chemical breakdown of its constituents resulting in a progrressively lower capacity over time. Overcharging can also cause a capacity loss, since once the battery is fully charged, the charging current begins working to electrolyze the water in the electrolyte. The only real fix is a new battery, I’m afraid.
It really depends on the battery type. I have rescued some NiMHs by going thru a deep discharge cycle a couple times: Turn off all power savings and let it run for a while. Some makers supply a battery learning program that does something like this.
LiOns, those just plain go bad with not much help in fixing them.
How long have you been using this battery. Most notebook batteries regardless of formulation give about a year to two years at most before they turn to crap.
Any decent battery charger should have a discharge cycle before charging.
Some call it “memory.” It is a knee in the curve of available voltage and current. Routinely discharging a battery fully before charging it will flatten the knee in that curve.
So, I should occasionally completely discharge my laptop battery to help it last longer? I was told this, and I do this occasionally, but would I be better off doing it on a regular basis (every other month or so)?
“Completely discharging” batteries of any type is never a good idea. The kind of discharge cycling I talk about is to get to the point where the device won’t start up anymore. There’s still quite a few volts left. E.g., a 1.2V cell might be drained down to .8V. Multiply by the number of cells in the battery to see that “completely” doesn’t apply.